A Dichoptic Edge Effect Resulting from Binocular Contour Dominance

If one eye sees a bright field on a dark surround while a homogeneous background is presented to the other eye, then a distinct dark zone appears at the outer borders of the field.If the surround is coloured, then the zone is of corresponding hue. The effect disappears if the edge of the field can be fused with a bar of appropriate contrast. The influence of parameters such as pattern contrast and size were studied quantitatively. A model is proposed relating the effect to receptive-field organisation and the fusion process.